Linear apparatus for high speed production of air-laid non-woven webs

Abstract

A non-woven fibrous web is continuously air-laid by directing a fluid stream of fibers from a rotating spinner against the inner surface of a moving foraminous belt which travels in an arc substantially around the circumference of the spinner, with suction being applied to the outer surface of the foraminous belt to facilitate uniform fiber lay-down and to remove the fluid.

What is claimed: 
     
       1. Apparatus for producing a non-woven fibrous web comprising: a flexible, endless foraminous belt; drive means for causing continuous longitudinal movement of said belt; guide means engaging said belt to cause it to form a closed substantially enveloping loop while maintaining a uniform profile across the belt width; supply means for providing a stream of fibers suspended in a fluid; spinner means connected to said supply means and positioned inside the arc formed by the looped belt for directing a fiber-containing fluid stream toward the interior surface of said arc section of said belt uniformly across the width of said belt around a substantial portion of the circumference of said arc section of said belt; said spinner means comprising a rotatable member having the plurality of arcuate channel openings spaced along its length and around its periphery, each of said arcuate channel openings communicating with a separate conduit extending parallel to the axis of the central shaft of said rotatable member from said arcuate channel opening to an end of said rotatable member where said conduit receives a portion of the fiber-containing stream from said supply means; and exhaust means mounted in coaxial relationship with at least a portion of the outer circumference of the arc section of said belt to apply suction through said belt for the purpose of promoting rapid deposit of fibers on said interior surface of said arc of said belt while removing said fluid through said belt. 
     
     
       2. Apparatus according to claim 1 wherein the arcuity of said arcuate channels is such that said fiber-laden stream is directed in a direction away from and opposite to the direction of rotation of said rotatable member. 
     
     
       3. Apparatus according to claim 1 wherein said rotatable member rotates in a direction opposite to the direction of movement of said belt. 
     
     
       4. Apparatus according to claim 1 wherein said rotatable member rotates the same direction as the direction of movement of said belt. 
     
     
       5. Apparatus according to claim 1 wherein certain of said arcuate channel openings are connected by a portion of said conduits to supply means at one end of said rotatable member and the remaining arcuate channel openings are connected by the remaining conduits to supply means at the other end of said rotatable member. 
     
     
       6. Apparatus according to claim 5 wherein the arcuate channel openings connected to an individual end are spaced along the entire length of said rotatable member. 
     
     
       7. Apparatus according to claim 1 wherein said exhaust means comprises a plenum connected to a suction source and communicating with the exterior surface of said foraminous belt through a perforate suction control plate. 
     
     
       8. Apparatus according to claim 7 wherein said perforate suction control plate has associated with its control means for selectively controlling the degree of perforation of said perforate suction control plate. 
     
     
       9. Apparatus according to claim 8 wherein said control means consists of moveable imperforate bands encircling said perforate suction control plate, which bands can be adjusted to cover any desired percentage of the perforations in said control plate. 
     
     
       10. Apparatus according to claim 8 wherein said control means consists of removeable plugs which can be inserted in any desired percentage of the perforations in said control plate and in any desired configurations. 
     
     
       11. Apparatus according to claim 8 wherein said peforate suction control plate consists of a plurality of separate imperforate principal bands aligned parallel with the axis of said exhaust means and with one another, and said control means consists of moveable imperforate control bands encircling said principal bands and cooperating with said principal bands to form rectangular perforation, the size of said perforation being adjustable as desired. 
     
     
       12. Apparatus according to claim 1 having a web stripping means to facilitate the removal of said web from said belt. 
     
     
       13. Apparatus according to claim 1 wherein said foraminous belt has edge strips with perforations therein spaced to be engaged by a drive means.